Energy is the ability to do work and to perform any task. We need energy for each body function, as well as for sleeping, resting and other activities. Every single cell in the body requires a constant supply of energy.
Food is the fuel that supplies energy to the body. Much like petrol in a car, the food is burned in the body cells and, in the process, heat and energy are released and allow the body to work. Because oxygen is needed to burn the food, this process is known as oxidation.
Food Energy In body cells O2 How oxidation occurs in the body Energy requirements
The body needs a basic amount of energy to stay alive, and to keep vital organs such as the heart and digestive system working. The basal metabolic rate (BMR) is the minimum amount of energy needed to keep the body’s organs working. Extra energy is needed for any activities we do, such as walking, swimming or running. The more active the body, the more energy is used.
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Running/ football
Swimming/ squash
Dancing/ tennis
Cycling Walking briskly
Housework Walking slowly
Writing Standing Sitting Sleeping Kilocalorie use per hour 41
